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#include <bits/stdc++.h>
using namespace std;

int main() {
    ios_base::sync_with_stdio(false);

    int n;
    cin >> n;
    int cnt1 = 0;
    for (int i = 0; i < n; i++) {
        int a;
        cin >> a;
        if (a == 1) {
            cnt1++;
        }
    }
    
    cout << 2 - min(2, cnt1) << "\n";
    cout << "2\n1 2\n";
}